The presidential debate at Hofstra University gave voters their first glimpse of Donald Trump and Hillary Clinton together onstage, and while Clinton was considered by many to be the better debater, it’s unclear how much the prime-time spectacle will sway voters in her favor.

“It is questionable how much presidential debates really shift public opinion,” said David Schultz, a professor of political science at Hamline University and author of over 30 books, including “Presidential Swing States: Why Only Ten Matter.”

“Overall, Clinton should be judged the winner,” Schultz said, adding that the impact is yet to be seen.

Republican nominee Donald Trump and Democratic nominee Hillary Clinton face off during the first presidential debate at Hofstra University in Hempstead, N.Y., on Sept. 26. (PAUL J. RICHARDS/AFP/Getty Images)

“The best political science evidence is that the debates only shift a small number of voters.”

However, there are examples of good debate performances that shifted a significant amount of votes. Mitt Romney gained a net of 4.4 percentage points on Obama after he was overwhelmingly considered the winner of the first debate in 2012—but later lost those points. Bill Clinton saw the polls swing by 4.1 points in his favor after the town hall debate of 1992 where George H.W. Bush was seen as out of touch after looking at his watch.

Micah Cohen, political editor at polling website FiveThirtyEight, said that a small bump in the polls for Clinton would give her more of a cushion going into election day. She’s currently polling at 1 to 2 percent ahead of Trump, and, according to Cohen, could gain an extra one or two points given her debate performance.

“Historically, in the last 10 elections, debates haven’t moved the polls that much,” Cohen said, noting that 10 election cycles is a small sample size to draw a conclusion from.

A boost in the polls would most likely come from voters who up to now have said they will vote for Libertarian candidate Gary Johnson or Green Party candidate Jill Stein. Johnson is currently polling at 7.4 percent, according to a national polling average by the website RealClearPolitics, and Stein is polling at 2.4 percent.

The fact that neither Johnson nor Stein had the 15 percent polling average needed to be on the debate stage could mean voters will turn their attention to one of the two major party candidates.

The day after the debate, Trump declared himself the winner, based on online surveys taken by websites such as Breitbart, the Drudge Report, Time Magazine, CNBC, and Fox News. These polls, which are considered flawed given that one person can vote multiple times, counter the narrative by pundits who saw Clinton as the better candidate on the stage.

“I won every poll from last nights Presidential Debate—except for the little watched @CNN poll,” Trump wrote in a tweet shortly after the debate.

I won every poll from last nights Presidential Debate – except for the little watched @CNN poll.

Both candidates stuck to the game plan foreshadowed in the primary debates.

Trump was “aggressive and continued his rhetorical style that suited well during the Republican debates,” Schultz said. “He raised questions about Clinton’s honesty and stamina, and her views on some policy issues such as Iraq,” all of which are important issues to Trump’s base of voters.

This strategy is part of what helped his outsider candidacy so far. He gave his strongest performance in the first half of the debate, when he was asked about domestic issues such as jobs, trade, and economic policies and plans.

Clinton, however, did the most damage when she attacked Trump, which led to him spending time defending things he’d said previously. Three sticky points that came up in the debate were “birtherism,” tax returns, and Trump’s treatment of women.